Corrected entry: When Charlotte wakes up in the morning next to Harry, she turns over to talk to him. At this point, you can see that she is still wearing a simple gold wedding band on her right hand. This makes no sense, as she is completely divorced and already dating someone else. She wouldn't still be wearing her wedding ring from her marriage with Trey.

Correction:This most likely isn't her wedding ring, because she gave her old ring to Carrie in season 4 after her breakup with Aiden. Carrie needed to buy her apartment from Aiden, who purchased it when she realized her building was going co-op, and Charlotte gave her the ring from her wedding with Trey to help Carrie out. Women wear all different types of rings, and on Sex and the City, they always wear some sort of jewelry and have accessories.